UNJustice 1% problems... 99%

The money is a type of information that facilitates the transactions... but when you use these "invent" as a weapon...

Resources:

Richest 1% of people own nearly half of global wealth, says report | Business | The Guardian

World Hunger could be resolved...

Teen girls give an idea for a better germitaion of certain criops by some notrogen-fixin bacteria.

Resources:

Teen Girls Take Swipe At World Hunger With Google Science Fair Idea, Remind Us All To Dream Big

Water reserves will bring violen confrontations

Water is the most valuable resource in planet earth.

Resources:

Why global water shortages pose threat of terror and war | Environment | The Guardian

Robots than could kill...

No matter how it scares you... of course is not really a god idea but... it happens.
There are a lot of machines used my army all around the world and also have weapons not only sensors.

Sources

Should a robot decide when to kill? | The Verge
X-47B | Ultimate Weapons | American Heroes Channel
Campaign to Stop Killer Robots